Benchmark oil for April delivery was down 12 cents to $90.31 a barrel at midday Bangkok time in electronic trading on the New York Mercantile Exchange. The contract fell 39 cents to close at $90.43 per barrel on the Nymex on Wednesday.

The death on Tuesday of President Hugo Chavez of Venezuela, which sits on the world's second-largest oil reserves, has had little immediate effect on the price of oil so far.

Chavez oversaw a decline in oil production during his 14 years as the leader of Venezuela. Traders are anxious to see if the new government invites foreign investment in Venezuela's oil industry and is able to boost output.

"Over the longer term, changes in policy towards the energy sector might eventually allow Venezuela's oil production to return to the much higher levels seen in the late 1990s," Julian Jessop of Capital Economics wrote in an email commentary.

A report from the Federal Reserve issued Wednesday showed the U.S. economy strengthened across much of the country. The Fed's Beige Book report showed that auto sales, more hiring and the ongoing housing recovery helped the U.S. economy grow in the first two months of the year.

Also Wednesday, the U.S. Energy Information Administration said in its weekly report that U.S. oil supplies grew last week by 3.8 million barrels, or 0.4 percent, more than three times the increase that analysts expected. The nation's supply of crude is 10.3 percent above year-ago levels. And at more than 7 million barrels a day, U.S. oil production is at the highest level since the late 1990s.

Brent crude, used to price many kinds of oil imported by U.S. refineries, fell 15 cents to $110.91 a barrel on the ICE Futures exchange in London.